The area of Šmarna gora and Grmada has a moderate continental climate, with Alpine, Mediterran and even Panonian affecting it at times. The average yearly temperature is 8°C. The average annual precipitation is 1340 mm. On average the rainiest months are June, followed by August, September and October.
Ljubljana Basin is known for heat inversion, therefore while the valley is many times foggy, it is sunny on the top.
Some saying that are good to remember:
- When Šmarna gora gets a hat (from clouds or fog), it will continue to rain.
- When there is a thick fog in the valley, the top of Šmarna gora is bathing in the sun.
- When at rain the clouds move up the Sava, there will be more rainy days.